APPLICATION SWITCH SYSTEM AND APPLICATION SWITCH METHOD

• US 20110289230A1
• Filed: 08/02/2011
• Published: 11/24/2011
• Est. Priority Date: 02/03/2009
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: UENO, Hiroshi
• Granted Patent: US 8,930,552 B2
• Time in Patent Office: Days
• US Class Current: 709/228
• CPC Class Codes: H04L 45/42 Centralised routing
• CPC Class Codes: H04L 67/1038 Load balancing arrangements to avoid a single path through a load balancer
• CPC Class Codes: H04L 67/563 Data redirection of data network streams
• CPC Class Codes: H04L 69/161 Implementation details of TCP/IP or UDP/IP stack architecture; Specification of modified or new header fields
• CPC Class Codes: H04L 69/163 In-band adaptation of TCP data exchange; In-band control procedures
• CPC Class Codes: H04W 40/22 using selective relaying for reaching a BTS [Base Transceiver Station] or an access point

Abstract

In data processing of network traffic (a communication amount), relay processing is distributed in a wide area. Specifically, an application switch system which controls a connection between a plurality of client terminals and a plurality of servers, is provided with at least one switch, a relay unit configured to perform protocol relays; and a controller. The controller is provided with a section for performing a centralized control on a route table used to determine a destination in the switch; a section for controlling relay processing of the relay unit; a section for selecting one server as a connection destination from the plurality of servers; a section for selecting a route which links between one client terminal of the plurality of client terminals and the selected server, and which contains the relay unit, and for setting the selected route to the route table in the switch; and a section for setting relay information used when the relay unit performs the protocol relay, to the relay unit.

Claims

1. An application switch system comprising:

a switch configured to control a connection between a plurality of client terminals and a plurality of servers which exist on a network;

a relay unit configured to perform a protocol relay; and

a controller,

wherein said controller comprises;

a section configured to perform a centralized control on a route table used to determine a destination in said switch;

a section configured to control relay processing of said relay unit;

a section configured to select one server as a connection destination from said plurality of servers;

a section configured to select a route which links between one client terminal of said plurality of client terminals and said selected connection destination server, and which contains said relay unit, and set the selected route to the route table in said switch; and

a section configured to set relay information used when said relay unit performs the protocol relay, to said relay unit.

2. The application switch system according to claim 1, wherein said controller further comprises a section configured to select said relay unit arranged in a position nearest to said selected server as the connection destination on said network route, when a plurality of said relay units exist on said network.

3. The application switch system according to claim 1, wherein said controller further comprises a section configured to select said relay unit arranged in a position nearest to said client terminal as a connection source on said network route, when a plurality of said relay units exist on said network.

4. The application switch system according to claim 1, wherein said controller further comprises:

a section configured to determine a distribution destination of an application;

a section configured to select said relay unit arranged in a position nearest to said one server as the distribution destination of said plurality of servers and select the route which contains said selected relay unit; and

a section configured to perform hand-off processing to said selected relay unit.

5. The application switch system according to claim 1, wherein said controller further comprises:

a section configured to select said server of at least one from among said plurality of servers based on a destination address of a packet transmitted from said one client terminal of said plurality of client terminals; and

a section configured to select the route which links said one client terminal of said plurality of client terminals and said selected server and which contains said relay unit, and set the selected route to said route table in said switch.

6. The application switch system according to claim 5, wherein said controller further comprises:

a section configured to select said relay unit having the smallest processing load from among a plurality of relay units which exist on a common route from said one client terminal of said plurality of client terminals to said selected server, when said plurality of relay units exist on said network.

7. The application switch system according to claim 5, wherein said controller further comprises:

a section configured to terminate a connection from said client terminal to take out a message when a protocol of a relay object is TCP (Transmission control Protocol), and select said one server as the connection destination from among said plurality of servers corresponding to a destination address of a TCP connection request based on a content of the message; and

a section configured to issue the TCP connection request to said selected server, and perform hand-off of header conversion information used for relay of a plurality of TCP packets to said relay unit.

8. The application switch system according to claim 5, wherein said controller comprises:

an address conversion table in which correspondence data between the destination address of the packet and an address of said one relay unit is registered as the relay information used when the protocol relay is performed; and

a section configured to refer to said address conversion table when the packet is received, to convert the destination address of the received packet to the address of said relay unit.

9. The application switch system according to claim 1, wherein said relay unit comprises:

a section configured to select a TCP header of the received packet to be relayed when the protocol of a relay object is TCP (Transmission control Protocol).

10. The application switch system according to claim 5, wherein said relay unit comprises:

a section configured to perform TCP termination of the message to be relayed when the protocol of a relay object is TCP (Transmission control Protocol);

a section configured to select said one server from among said plurality of servers based on the content of the message subjected to the TCP termination;

a section configured to establish the TCP connection with said selected server; and

a section configured to relay the message subjected to the TCP termination to said selected server.

11. The application switch system according to claim 1, wherein said plurality of servers, said switch and said relay unit are virtual machines on a computer.

12. A controller comprising:

a section configured to perform a centralized control on a route table used to determine a destination in a switch;

a section configured to control relay processing of a relay unit;

a section configured to select one server as a connection destination from a plurality of servers;

a section configured to select a route which links between one client terminal of a plurality of client terminals and said selected connection destination server, and which contains said relay unit, and to set the selected route to the route table in said switch; and

a section configured to set relay information used when said relay unit performs the protocol relay, to said relay unit.

13. An application switch method comprising:

controlling, by a switch, a connection between a plurality of client terminals and a plurality of servers which exist on a network;

performing a protocol relay by a relay unit;

performing a centralized control on a route table used to determine a destination in said switch by a controller;

controlling relay processing of said relay unit by said controller;

selecting one server as a connection destination from said plurality of servers by said controller;

selecting, by said controller, a route which links between said one client terminal of said plurality of client terminals and said selected server, and which contains said relay unit;

setting, by said controller, the selected route to a route table in said switch; and

setting, by said controller, relay information used when said relay unit performs the protocol relay, to said relay unit.

14. The application switch method according to claim 13, further comprising:

selecting as said selected relay unit, by said controller, said relay unit arranged in a position nearest to said selected server as a connection destination on the network route, when said plurality of relay units exist on said network.

15. The application switch method according to claim 13, further comprising:

selecting as said selected relay unit, by said controller, said relay unit arranged in a position nearest to said one client terminal as a connection source on said network route, when said plurality of relay units exist on said network.

16. The application switch method according to claim 13, further comprising:

performing a determination of a distribution destination of an application by said controller;

selecting said relay unit arranged in a position nearest to said selected server as the distribution destination of said plurality of servers by said controller;

selecting the route which contains said selected relay unit by said controller; and

performing a hand-off to said selected relay unit by said controller.

17. The application switch method according to claim 13, further comprising:

selecting said server of at least one from among said plurality of servers based on a destination address of a packet transmitted from said one client terminal of said plurality of client terminals by said controller;

selecting said route which links between said one client terminal of said plurality of client terminals and said selected server, and which contains said relay unit, by said controller; and

setting the selected route to said route table in said switch.

18. The application switch method according to claim 17, further comprising:

selecting as said selected relay unit, by said controller, said relay unit having the smallest processing load from among a plurality of relay units which exist on a common route from said one client terminal of said plurality of client terminals to said selected server, when said plurality of relay units exist on said network.

19. The application switch method according to claim 17, further comprising:

performing TCP termination of a connection from said one client terminal to take out a message by said controller;

selecting said one server as a connection destination from among said plurality of servers corresponding to a destination address of a TCP connection request based on the content of the message, by said controller, when the protocol of a relay object is TCP (Transmission control Protocol);

issuing the TCP connection request to said selected server by said controller; and

performing hand-off of header conversion information used for relay of a plurality of TCP packets on said relay unit by said controller.

20. The application switch method according to claim 17, further comprising:

setting, by said controller, correspondence data of the destination address of the packet and an address of said relay unit, to the address conversion table, as the relay information used when the protocol relay is performed; and

referring to said address conversion table, by said controller, when receiving the packet, to convert the destination address of the received packet to the address of said relay unit.

21. The application switch method according to claim 13, further comprising:

converting, by said relay unit, a TCP header of the received packet to be relayed when the protocol of a relay object is TCP (Transmission control Protocol).

22. The application switch method according to claim 17, further comprising:

performing, by said relay unit, TCP termination of the message to be relayed when the protocol of a relay object is TCP (Transmission control Protocol);

selecting, by said relay unit, said one server from said plurality of servers based on the content of the message subjected to the TCP termination; and

establishing, by said relay unit, the TCP connection with said selected server; and

relaying, by said relay unit, the message subjected to the TCP termination to said selected server.

23. The application switch method according to claim 13, further comprising:

realizing said plurality of servers, said switch and said relay unit as applications of virtual machines on a computer; and

connecting between said switch and said relay unit through an internal network of said computer.

24. A computer-readable non-transitory storage medium which stores a computer-executable program code to attain an application switch method which comprises:

making a plurality of servers, a switch, and a relay unit operate as applications of virtual machines on a computer;

controlling, by said switch, connections between a plurality of client terminals and said plurality of servers which exist on a network;

performing, by said relay unit, a protocol relay;

performing a centralized control on a route table used to determine a destination in said switch;

controlling relay processing of said relay unit;

selecting one server as a connection destination from said plurality of servers;

selecting a route which links between one client terminal from said plurality of client terminals and said selected server, and which contains said relay unit;

setting the selected route to a route table in said switch; and

setting relay information used when said relay unit performs the protocol relay, to said relay unit.

25. The computer-readable non-transitory storage medium according to claim 24, wherein the application switch method further comprises:

selecting as said selected relay unit, said relay unit arranged in a position nearest to said server as a connection destination on the network route, when said plurality of relay units exist on said network.

26. The computer-readable non-transitory storage medium according to claim 24, wherein the application switch method further comprises:

selecting as said selected relay unit, said relay unit arranged in a position nearest to said one client terminal as a connection source on said network route, when said plurality of relay units exist on said network.

27. The computer-readable non-transitory storage medium according to claim 24, wherein the application switch method further comprises:

performing a determination of a distribution destination of an application;

selecting the relay unit arranged in a position nearest to said selected server as the distribution destination of said plurality of servers;

selecting the route which contains said selected relay unit; and

performing a hand-off to said selected relay unit.

28. The computer-readable non-transitory storage medium according to claim 24, wherein the application switch method further comprises:

selecting, by said controller, said selected server of at least one from among said plurality of servers based on a destination address of a packet transmitted from said one client terminal of said plurality of client terminals;

selecting, by said controller, the network route which links between said one client terminal of said plurality of client terminals and said selected server, and which contains said relay unit; and

setting the selected route to said route table in said switch.

29. The computer-readable non-transitory storage medium according to claim 28, wherein the application switch method further comprises:

selecting as said selected relay unit, by said controller, said relay unit having the smallest processing load from among a plurality of relay units which exist on a common route from said one client terminal of said plurality of client terminals to said selected server, when said plurality of relay units exist on said network.

30. The computer-readable non-transitory storage medium according to claim 28, wherein the application switch method further comprises:

performing, by said controller, TCP termination of a connection from said one client terminal to take out a message;

selecting, by said controller, said one server as a connection destination from among said plurality of servers corresponding to a destination address of a TCP connection request based on the content of the message, when the protocol of a relay object is TCP (Transmission control Protocol);

issuing, by said controller, the TCP connection request to said selected server; and

performing, by said controller, a hand-off of header conversion information used for relay of a plurality of TCP packets on said relay unit.

31. The computer-readable non-transitory storage medium according to claim 28, wherein the application switch method further comprises:

setting, by said controller, correspondence data of the destination address of the packet and an address of said relay unit, to the address conversion table, as the relay information used when the protocol relay is performed; and

referring to said address conversion table, by said controller, when receiving the packet, to convert the destination address of the received packet and the address of said relay unit.

32. The computer-readable non-transitory storage medium according to claim 24, wherein the application switch method further comprises:

converting, by said relay unit, a TCP header of the received packet to be relayed when the protocol of a relay object is TCP (Transmission control Protocol).

33. The computer-readable non-transitory storage medium according to claim 28, wherein the application switch method further comprises:

performing, by said relay unit, TCP termination of the message to be relayed when the protocol of a relay object is TCP (Transmission control Protocol);

selecting, by said relay unit, one server from said plurality of servers based on the content of the message subjected to the TCP termination; and

establishing, by said relay unit, the TCP connection with said selected server; and

relaying, by said relay unit, the message subjected to the TCP termination to said selected server.